In particles removal with extremely high filtration efficiency and the ability to block submicron airborne particles by a sieving mechanism is provided. This novel nanoporous filter advantageously combines extremely high transmittance for visible light and ultraviolet light, reusability after cleaning or disinfection by ultraviolet irradiation or simple washing, a customizable sieving pore size ranging from a few nanometers to 500 nanometers, and the ability to carry bactericidal, virucidal or other reagents or particles on the nano or micro scale.

A provided air filter medium is an air filter medium including a porous fluorine resin membrane, the air filter medium further including: a glass filter medium layer. The glass filter medium layer and the porous fluorine resin membrane are placed in this order from upstream to downstream of the air filter medium configured to allow an air flow to pass through the air filter medium. At a surface of the glass filter medium layer on an upstream side in a direction of the air flow, a carbon-to-silicon ratio (C/Si) evaluated by X-ray fluorescent analysis is 0.020 or more. This air filter medium is suitable for reducing a pressure drop increase even in an environment including liquid particles such as oil mist.

A multi-layered replaceable filter assembly (100) and a microfilter assembly (200) for providing safety from external exposure. The multi-layered micro filter assembly includes plurality of filter membranes. A first filter membrane (104) prevents particles greater than 10 micron from entering the multi-layered replaceable filter assembly (100). A second filter membrane (106) has embedded activated carbon that destroys micro-organisms including viruses and bacteria. As we go further downstream, the fiber density per cm keeps increasing with the filter membranes. A fifth filter membrane (112) made up of a combination of crabyon fiber and electro-spun nano fibers provides comfort and anti-allergic effect. A sixth filter membrane (114) lowers the velocity of air that occurs from breathing and a method thereof.

A filter assembly has a housing. The housing has an inner body and an outer body surrounding at least a portion of the inner body. The inner body has a base extending in a lateral direction and a first sidewall extending axially outward from the base. The inner body defines a cavity. The first sidewall defines a perimetric surface around the cavity. A first filter media extends across the perimetric surface and across the cavity. An adsorbent is disposed in the cavity. The outer body has a second sidewall laterally outward from and surrounding the first sidewall. The second sidewall spans at least 50% of the axial length of the first sidewall. The outer body has a first axial end and a second axial end and a retainer portion extending laterally inward from the first axial end. The retainer portion is positioned axially outward from the first filter media.

A system including a pressure accommodating assembly having a body with a first side and a second side. The assembly further includes a gas permeable membrane coupled to the body and configured to allow gases to permeate therethrough to thereby move from the first side to the second side. The assembly also includes a pressure relief valve coupled to the body, wherein the pressure relief valve is biased to a closed position to generally block a flow of gases therethrough and is configured to move to an open position when there is a predetermined pressure differential thereacross to allow gases to flow therethrough to move from the first side to the second side. The pressure accommodating assembly is configured to maintain its structural integrity after being exposed to a temperature of about 500° C.

An electronic microbicidal air filter is provided as an ambient air filter in aeration supports or ventilation grids and as an air filter for PPE protection masks. The filter includes an UVC luminaire (2), a power module (3), activation sensors (4), internal structure (5) with walls defining filtering chambers (6) with exposure membranes (7) sandwiched between the chambers (6) under the luminaire (2), so that the chambers (6) determine a winding zigzag path for the air that passes therethrough, while the particles carried by the air are irradiated by the luminaire (2) directly. The functional elements in the internal structure (5) of chambers (6) are integrated in an encapsulation (9) that surrounds the external part of the assembly and defines a sealed space for the functional and support elements at the ends of the structure (5).

A mask is provided according to the present application. The mask includes a mask body with filtering performance and a flexible support frame. The support frame is arranged in the mask body and connected to the mask body. The mask body includes a first filter area corresponding to the support frame and a second filter area surrounding the support frame. While the mask is in use, the support frame supports the mask body, so that the first filter area and at least part of the second filter area are spaced apart from the user's face. When the mask according to the present application is worn, the support frame separates the whole first filter area and at least part of the second filter area of the mask body from the wearer's face, which significantly increases the filter area of the mask and makes the wearer's breathing smoother.

An air filter medium includes a collection layer, an air-permeable adhesive layer, and a porous fluorine resin membrane in this order from upstream to downstream of the filter medium. An initial pressure drop of the filter medium at a permeate flow rate of 5.3 cm/sec is 250 Pa or less. When a test is performed in which polydisperse polyalphaolefin particles having a peak in number in a particle size range of 0.1 to 0.2 μm are allowed to pass through the filter medium at a concentration of 0.2 to 0.5 g/m.sup.3 and a linear velocity of 5.3 cm/sec, the holding amount is 43.0 g/m.sup.2 or more from a moment when the holding amount reaches 20 g/m.sup.2 to when a moment the pressure drop reaches PD.sub.1+120 Pa, where PD.sub.1 is the pressure drop of the filter medium at the moment when the holding amount reaches 20 g/m.sup.2.

Disclosed herein are filtration articles comprising a porous ceramic structure comprising a plurality of channels separated by a plurality of porous interior walls, and a nanomembrane disposed on at least a portion of a surface of the porous ceramic structure, wherein the nanomembrane comprises nanoparticles of at least one inorganic oxide, and wherein the nanoparticles are present in a concentration ranging from about 0.001 g/L to about 1 g/L based on the total volume of the porous ceramic structure. Methods for making such filtration articles and methods for filtering a particulate from a fluid using such filtration articles are also disclosed herein.

Disclosed herein are filtration articles comprising a porous ceramic structure comprising a plurality of channels separated by a plurality of porous interior walls, and a nanomembrane disposed on at least a portion of a surface of the porous ceramic structure, wherein the nanomembrane comprises nanoparticles of at least one inorganic oxide, and wherein the nanoparticles are present in a concentration ranging from about 0.001 g/L to about 1 g/L based on the total volume of the porous ceramic structure. Methods for making such filtration articles and methods for filtering a particulate from a fluid using such filtration articles are also disclosed herein.